How do I make a model resemble one with low poly count?
It would seem you want to create low-poly art. The best way to do this is to actually model these objects to achieve this look and quality and then texture them.

No amount of modifiers or tricks will get the same unique look. Also using modifiers can make animating, texturing or rigging very difficult and also destroy your mesh topology something that is key in lowpoly style characters/objects.

The Decimate modifier might be of some help though, it can reduce mesh geometry but it is not very flexible and generally unpredictable in how it does this when used on complex objects.

Also as bummzack points out below, alot of the detail say you see on low-poly models is mostly from the texture(s).